mercury allows you to take a fragment of code from some source (current line, selection, buffer), execute the code intelligently, and then write the result to some destination (message window, selection, register, new split).

Features include:

* choose the correct interpreter with the correct switches, given the filetype.
* execute it in a separate thread and terminate it after a timeout, so an endless loop will not freeze vim.
* some language specific smartness (e.g. handling imports).

Currently supports python, ruby and javascript (using node) with more to come soon, hopefully.